Concealed display

ABSTRACT

A wristwatch with analogue time display comprises a dial with a hatch (19), and a rotatable disc or hoop (10) bearing non-time indications. The disc is arranged in such a way that the indications provided thereon appear in the hatch via an opening provided in said disc and having a size which is equal to the size of each indication. Said opening reveals additional indications provided by an electro-optical display device (30) when said opening (21) coincides with said hatch (19).

The present invention concerns an analog wristwatch with a window in theface and a rotatable disc or ring bearing information other than timeindications, with the disc being designed to display information in thewindow.

Quartz analog time display watches, that is, watches using hands to showthe time and a disc to show the date or day of the week, preferably havethe same outward appearance as traditional mechanical watches.

For this type of product it is preferable to adapt and use an electronicmovement rather than a mechanical one, as the electronic movement offersimproved precision and longevity over the life expectancy of thebattery, rather than for the limited number of hours of energy stored inthe spring barrel of a mechanical watch. Using an electronic movementgives designers the same freedom as using a mechanical movement andallows a wide variety of product dress without affecting the basicfunction of time display (second, minute, hour, date, perhaps day of theweek, month or year).

The following prior art solutions have been proposed to integrate one ormore supplemental features into an electronic analog watch such as atimer, an alarm, or month, year, temperature display, etc.:

adding an electro-optical cell for numeric or alpha-numeric display nextto the watch face or in a window formed in the face;

placing an electro-optical cell of the same shape as the watch facewithin the face, said cell having a hole in the center through which theaxes of the watch hands may pass.

The disadvantages inherent in these embodiments impose seriouslimitations upon designers. Electro-optical cells are available in onlya very limited number of colors, and their shape as well as theappearance of the display characters can make the product unattractive,particularly for the high fashion market.

To overcome these disadvantages, the watch according to the invention ischaracterized in that the disc has at least one opening located in thesame place as a unit of information supplied thereon and makessupplemental information available when said opening corresponds withthe window.

According to a preferred embodiment, the supplemental information isprovided by a fixed electro-optical display means.

When the disc carries date information, the size of the opening in thedisc preferably corresponds approximately to a 1/32nd rotation.

When the disc is for displaying days of the week, the disc opening sizecorresponds essentially to a 1/8th rotation.

According to a particularly advantageous embodiment, the disc opening isessentially equivalent in size to the window in the watch face.

The watch according to the invention comprises control means for accessto the supplemental information displayed in said opening.

When the watch has a time set stem, said control means preferablyconsists of the time set stem.

The time set stem on the watch is preferably designed so thatspecialized manipulations activate the command for displayingsupplemental information in said opening.

The control means preferably consists of at least one button.

In another watch embodiment, the control means is automatic and isactivated by applying tension when changing the battery.

The present invention will be better understood with reference to thedescription of one preferred embodiment and one variation thereof, andto the attached drawing, in which:

FIG. 1 shows a partial view of the watch according to the invention inwhich the supplemental information accessible via the disc opening isconcealed;

FIG. 2 shows the watch of FIG. 1 with the opening and the windowsuperimposed;

FIG. 3 shows a view of another embodiment with the informationconcealed; and

FIG. 4 shows the watch of said other embodiment with the supplementalinformation displayed through the disc opening and the windowsuperimposed thereon.

In the embodiments described below with reference to the drawings, adisc displaying the date and/or day of the week is shown, which in oneposition presents an opening revealing an electro-optical displaydevice, said electro-optical display device being affixed beneath thewindow in the watch face and beneath the disc. This opening preferablyspans a 1/32nd rotation of the date disc, for example, between thethirty-one and the one, or spans a 1/8th rotation by the day-of-the-weekdisc, for example, between Sunday and Monday. When the opening coincideswith the window, a unit of information from the electro-optical displayappears. In all other positions this information is concealed by thedisc which has either the date numbers or the days of the week on itsupper surface, i.e., that surface of which 1/32nd or 1/8th, dependingupon the case, is visible through the window. Every position except theposition associated with the window corresponds to the conventionaldisplay of the date and/or day of the week.

Implementing such a device preferably necessitates some means forangular displacement of the date disc which is independent of the meansfor displacing the hands. The term "splitting the kinematic chain" intwo distinct portions is used. Such an arrangement, known in the art,provides for displacing one or more discs in one direction or anotherwithout interfering with time display by the hands, and must take placeregardless of the respective positions of the watch hands. A mechanicalanalog watch with a date or a day of the week disc is always equippedwith means for correcting angular position of said disc. As a generalrule, this consists of a mechanism connected with the time set stem sothat when it is in an intermediate axial position, perhaps extendedhalfway, one stem rotation causes date-to-date (or perhaps day-to-day)displacement of the corresponding disc. In this case the kinematic chainis also split. There is therefore nothing to prevent addition of anelectro-optical display, already described, to a mechanical watch, alongwith an associated electronic circuit regulating one or more additionalfunctions. One battery must be provided to supply only this portion.

In an electronic watch it is advantageous to provide a means forindexing the position of the disc or discs which, in association withthe electronic circuit of the watch, automatically positions the correctvalue opposite the window. In this case, the circuit actually includesan electronic memory for permanent storage of data relative to theactual position of the disc or discs.

In a simplified version without indexing means, displacing the disc ordiscs until the electro-optical display appears may be accomplishedmanually using the time set stem, as in a mechanical watch. This displaymight provide additional information such as a second time, i.e., thetime in another time zone.

In the embodiment which has no indexing system, when the month or weekchanges, the wearer uses the time set stem to manually advance theposition of the disc or discs for a 1/32nd or 1/8th additional turn,respectively, as in the mechanical version, to move from thethirty-first to the first day of the month or from Sunday to Monday andto bypass the disc opening.

The addition of a system indexing position for the disc or discsconnected to an electronic circuit controls the automatic advance of thediscs and bypassing the disc opening.

Splitting the kinematic chain, as described above, and providing aposition indexing system make it possible to achieve a watch know as aperpetual calendar watch. The electro-optical display offers aparticularly easy way to program the month and year into the electroniccircuit, necessary information for the perpetual calendar function.

With reference to FIGS. 1 and 2, an electronic watch comprising akinematic chain for time display (hour, minute and perhaps second hands)driven by a first motor (not shown) comprises a date disc 10 driven by asecond motor 11 which may be connected to an endless screw 12 engaging awheel 13 which meshes with said disc 10 or date ring. The motor iscontrolled by an electronic circuit 14 connected to a disc positionindexing device 15. This device comprises a contact 16 designed tocooperate with a peripheral projection 17 on disc 10.

The watch face 18 is partially shown with window 19. The windowdimensions are determined so that the dates 20 printed on disc 10 arevisible through the window in their entirety.

Between dates thirty-one and one, the disc comprises an opening 21essentially the same size as or slightly larger than window 19. Aspreviously described, this opening provides access to the supplementalinformation located in a fixed position beneath window 19 and which isconcealed when the opening does not coincide with the window.

In FIG. 1 three steps separate opening 21 from window 19 by and thesupplemental information display is effectively concealed by date disc10. In FIG. 2, opening 21 coincides with window 19 following theappropriate rotation of the date disc, and display device 30 appears inthe window. This device may consist, for example, of an opto-electronicunit which displays the number "03" in the embodiment shown. This deviceis controlled by electronic circuit 14 attached to printed circuit 31,with electronic circuit 14 being linked to display device 30 by means ofan electrical connection shown schematically by arrow 32. In thisposition contact 16 is closed and transmits the appropriate signal toelectronic circuit 14.

According to a preferred embodiment, the supplemental informationconsists of the number abbreviations for months, but may also consist ofany other information, such as ambient temperature, the time in a cityin another part of the world, etc.

FIGS. 3 and 4 show another embodiment in which the date disc is replacedby a day of the week disc. This day of the week disc comprises eightspaces, seven of which bear the names of seven days of the week and theeighth of which corresponds to opening 21. In this case opening 21 iselongate and essentially the same size as a 1/8th rotation of the day ofthe week disc. Window 19 also extends for the same length as to a 1/8throtation so that the entire name of the day is displayed. As shown inFIG. 3, the seven days are successively displayed in window 19 and theopening is concealed by the watch face for as long as the days aredisplayed. Conversely, when the day of the week disc moves to the eighthposition, window 19 and opening 21 coincide, thereby giving access tothe supplemental information located in a fixed position on the watchcase and located beneath window 19.

As shown in FIG. 4, in this embodiment the supplemental information maybe an entire date, for example Jul. 22, 1991, visible through window 19and opening 21.

As mentioned before, this supplemental information may be used forspecialized programming of the watch in the case of a perpetual calendarwatch. In this case, access to the opening and consequently to thesupplemental information display is specifically coded by specializedmanipulating of the electronic time set stem, S perhaps in threedifferent positions. Such an electronic time set stem is in effect acontact device which, in association with the electronic circuit of thewatch, regulates axial position, rotation and direction of rotation.Such a device is known in the art.

By way of example, when the stem is pushed down, rotation does notoccur. This is called the neutral position in which the watch functionsnormally.

When the time set stem is in intermediate axial position, rotationresults in an advance or a decrease of exactly one hour from the hourdisplayed by the watch hands, depending upon rotation direction.

When the time set stem is in fully extended axial position, rotationcontrols setting the watch hands for time display.

The electronic circuit is designed to order the motor driving the discto change the date when the hands reach midnight. When the date changesfrom the thirty-first to the first, the circuit advances the windowpositioned between these two dates and the watch works like aconventional watch.

A command must be given to the electronic circuit to reveal theelectro-optical display, with the circuit being designed to decode theorder and execute the command to displace the date disc until theopening coincides with the window. This command can be given by exertingpressure on a pushbutton, P thereby closing a contact connected to theelectronic circuit. However, for the sake of watch appearance, it ispreferable not to resort to using a button, but rather to usespecialized manipulations of the time set stem. When the stem is inextended position, rotating it five times within several secondsreplaces the button function. In this case the electronic circuitcomprises appropriate means for recognizing such a manipulation, whichputs the watch into programming mode.

When the opening in the date disc coincides with the watch face window,the electro-optical display is activated by the electronic circuit. Thisdisplay preferably is achieved by the use of an electro-optical cell.

When the stem is pushed down, the current date is displayed. Rotation inone direction causes an increment in date value and thus serves toprogram the desired date. Rotation in the other direction allows thespecialized stem manipulation described above, and the programmed datavalue is again displayed by the disc.

When the stem is in the middle axial position, the months from "01" to"12" are displayed: one clockwise rotation increases the display valueby one (+1), and one counterclockwise rotation decreases the displayvalue by one (-1). In this way the month is programmed.

When the stem is in the extended axial position, the display shows theyear in units of tens and ones (for example, 90 for the year 1990). Aclockwise or counterclockwise rotation respectively increases ordecreases the value displayed. In this way, the year is programmed. Whenthe stem has been pushed back down and the specialized manipulationdescribed above is complete, the electronic circuit commands the disc toreturn to the programmed position. Once the month and year have beenprogrammed, the electronic circuit is then able to control data discadvancement in accordance with the principles of a perpetual calendar.

When the window is located on the day of the week disc, as shown inFIGS. 3 and 4, the entire date--day, month and year--is displayeddirectly, thereby facilitating control of the programming operations.

We claim:
 1. A wristwatch with analog time display comprising a watchface with a window, said watch face carrying indicia on a first surfacethereof and having a rotatable disc supplying information relating to atleast one of a day of a week and a date of a month located adjacent asecond opposed surface of said watch face, said information beinglocated on a peripheral zone of said rotatable disc and currentinformation concerning at least one of a current day of a week and acurrent date of a month being displayable through said window in saidwatch face,wherein said rotatable disc (10) has at least one opening(21) formed therein at a peripheral zone adjacent the peripheral zonecarrying said information and supplemental information is displayablevia a display device through said opening (21) when said opening (21)coincides with said window (19).
 2. A watch according to claim 1,wherein said display device comprises a fixed electro-optical displaydevice (30) located adjacent the second surface of said watch face withsaid rotatable disc (10) located between said electro-optical displaydevice (30) and said the second surface of said watch face.
 3. A watchaccording to claim 1, wherein said information supplied by saidrotatable disc (10) consists of dates of the month (20) and said opening(21) formed in said rotatable disc spans a space substantially equal toa 1/32nd of a rotation of said rotatable disc.
 4. A watch according toclaim 1, wherein said information supplied by said rotatable discconsists of days of the week and said opening (21) formed in saidrotatable disc spans a space substantially equal to a 1/8th of arotation of said rotatable disc.
 5. A watch according to claim 1,wherein said opening (21) formed in said rotatable disc is substantiallyequivalent in size to said window (19) formed in said watch face.
 6. Awatch according to claim 1, wherein said watch further comprises controlmeans for programming said supplemental information to be displayed viasaid display device through said opening.
 7. A watch according to claim6, wherein a time set stem comprises a portion of said control means. 8.A watch according to claim 7, wherein said time set stem, when speciallymanipulated, activates a command to allow programming of saidsupplemental information to be displayed via said display device throughsaid opening.
 9. A watch according to claim 6, wherein said controlmeans consists of at least one pushbutton for closing a contact to allowprogramming of said supplemental information.
 10. A watch according toclaim 6, wherein a motor drives said rotatable disc to display currentinformation concerning at least one of the current day of the week andthe current date of the month and movement of said motor is controlledby a programmable electronic circuit (14).
 11. A watch according toclaim 10, wherein said control means is automatically activated byexerting pressure when changing said battery.